Applicable Field in Industries
The present invention relates to an infrared-ray temperature measuring apparatus wherein the surface temperature is displayed in response to the quantity of radiated infrared rays by receiving the infrared rays radiated from a portion whose temperature is to be measured.
As for the conventional infrared-ray temperature measuring apparatus of this kind, the apparatus described in the Japanese Utility Model Application No. 21205/1984 can be cited. Such an infrared-ray temperature measuring apparatus has a configuration wherein an infrared sensor which receives the infrared rays from the temperature measuring portion and outputs a signal responding to the temperature of the portion whose temperature is to be measured, a display part which displays the temperature of the temperature measuring portion by an output of that infrared sensor and a position determining means for determining the position at which the above-mentioned infrared sensor is to be disposed with a distance kept from the temperature measuring portion are provided, the position determining means is constituted with a first and a second light sources whose visible rays cross each other, and the position at which the above-mentioned infrared sensor is to be disposed is determined so that the cross point is positioned on the temperature measuring portion, and thereby the infrared sensor can be disposed simply at the position where the temperature of the temperature measuring portion can be measured accurately in a non-contact state.
However, the conventional infrared-ray temperature measuring apparatus has a configuration that the temperature measuring portion and the infrared sensor are disposed with a predetermined distance kept apart from each other by employing an optical system composed of a light source such as the light emitting diode or the like, therefore having a problem that the apparatus become large-sized as a whole.
Also, as the infrared-ray temperature measuring apparatus, an apparatus is publicly known by the specification of the U.S. Pat. No. 3,777,568, which provides a housing composed of a non-transparent material, having an opening formed at one end thereof, an infrared sensor which is disposed in the above-mentioned housing opposite to the above-mentioned opening, and a distance keeping member which is installed to keep the above-mentioned infrared sensor a predetermined distance apart from the temperature measuring portion.
The infrared-ray temperature measuring apparatus described in this literature has such problems that it is not suitable for measuring the body temperature because the tip of the distance keeping member is formed in a sharp shape, and also when measuring the temperature with this infrared-ray temperature measuring apparatus brought in contact with the temperature measuring portion, the angle made by the center of the sight of the infrared sensor and the temperature measuring portion is not constant and thereby the output from the infrared sensor differs every time the temperature is measured. Also, this apparatus has an additional problem that since the distance keeping member is located in the sight of the infrared sensor, the temperature of the distance keeping member is to be detected, and the temperature of the distance keeping member is varied due to a contact with the temperature measuring portion and thereby the output of the infrared sensor is not stabilized.